A surprising result to come out of the REBELS survey was the serendipitous detection of two dust-obscured galaxies at \(z\simeq 7\)  that have no optical counterparts in deep HST imaging [1]} – this implies SEDs and dust attenuations similar to those of the dustiest known galaxies, sub-millimetre galaxies, but in galaxies at much higher redshifts and lower stellar masses than typical SMGs. ALMA observations are not only revealing that there is a variety of dust obscuration at high-redshifts, but that there might be a hidden population of dusty galaxies at the EoR that we did not know about before (similar to optically-dark galaxies seen at lower redshifts; e.g., [2]}, [3]}). [1]} estimate that these dusty galaxies could contribute 10 to 25% of the total cosmic SFR density at \(z>6\) . This intriguing population needs further study, and these sources are prime targets for JWST follow-up.
